Pneumatic action.



H. BAINTON.

PNEUMATIC ACTION.

APPLICATION FILED JAN. 19, I914.

1 172,250. Patented Feb.- 22, 1916.

A2 5 l w 78 75 44 23 P 4 44 20 3 /7 VA) V 5 HARRY BAINTON, OF NEW YORK, N. Y.

PNEUMATIC ACTION.

Specification of Letters Patent.

. Patented Feb. 22, 1916.

Application filed January 19, 1914. Serial No. 813,037.

To all whom it may concern:

Be it known that I, HARRY BAINTON, a citizen of the United States of America, re-

siding in New York, in the State of New York, have invented certain new and use ful Improvements in Pneumatic Actions, of which the following is a specification.

The object of the present invention is to improve the player actions employed in mechanical musical instruments, and more particularly in pneumatic pianos.

Hitherto the repair of some of the parts of such an action necessitated the removal of many other parts and the practical dismantling of the entire action before access could be had to the part to be repaired.

In the present invention this difficulty is overcome by making a separate valve-action for each note and mounting these detachably on a detachable channel-rail. Thereby any individual valve-action may be independently removed, or, the entire set mounted on the rail may be removed together with the latter. Each separate valve-action has its separate pneumatic which is removable with it from the channel-rail, and independent means are provided for retaining each abstract rod in raised position so that the same does not drop out of position when the valve-action which normally sustains it is removed.

The invention also includes means for improving the working and regulation of the valve-action. The valve-seat is made of noncorrosive material having an extremely smooth surface, such for instance as glass, and guides, made integral with the valveseat, are provided for retaining and guiding the valve. The bleeder-opening from the chamber of the valve-casing to the trackerduct is made capable of regulation in size. The stroke of the pneumatic is regulated by a screw so placed as to be easily accessible from the frontof the action without displacing any parts.

In the accompanying drawings, Figure 1 shows in elevation a portion of the playeraction of a piano, embodying.th e'invention, Fig- 2 is a vertical longitudinal section on a larger scale through one of the valve-actions, Fig. 3 is a horizontal section on line 33 of Fig. 2, Fig. 4 is a vertical section on line 44 of Fig. 1, with one of the channel-rails omitted, and Fig. 5, is a perspective view of the valve-seat.

Similar reference numerals indicate cor responding parts in all the figures.

The pneumatic devices of the action comprise vertical supporting side-members 10, 11, containing'the trunks 13, and horizontal channel-rails 12 having therein suctionchannels 73. The channel-rails are detachably secured to the vertical members 10 and 11 by being inserted at their ends into,horizontal recesses or sockets 55 in said members 10 and 11, and retained therein at each end by an exterior thumb-nut 56 on the projecting front end of a clamping-bolt 57 which extends through the suction-channel 73 and trunk 13 and is secured at its rear end to the vertical supporting member. Connection of thesuction-channel 73 with the trunk 13 is made by'means of a bushing of brass or other material extending through the rear wall of the channel-rail and communicating with the trunk, as seen in Fig. 4. The trunks 13 are connected with any suitable source of suction.

The valve-carrying portion of the action comprises a casing 20 having therein a suction-chamber 14, which communicates by an opening 15 with the channel 73. In said opening 15 is a bushing 16, havin a crossbar 17. A thumb-screw 18 is threa ed in the cross-bar and extends upwardly through the channel and out at the top of the channel-rail and is provided at the top of the same with a knurled head 27 for being readily turned by hand.

The casing 20 is provided with a pneumatic-duct 21, and between the same and the suction-chamber 14 is the'valve 23, which is mounted on a valve-stem 24 and supported at its lower end on a diaphragm 25 of larger superficial areathan the opening 26 from the suction-chamber to the pneumatic-duct- The space below the diaphragm communicates by a tracker-duct 30 with the flexible tube 42 leading to the tracker-bar of the instrument, an angular brass connecting-tubeor nipple 43 making the connection, as clearly shown in Fig. 2. The bottom of the valve-casing 20, forms also the upper or stationary member of the pneumatic, 33. The movement of the pneumatic in closing direction is limited by an adjusting-screw 34 which is threaded in the movable wall 35 of the pneumatic, and which thereby has its head exposed at the extreme lower portion of the action, so that it may be readily gotten tracker-tube l2 from the nipple the channel-rail 12. The valve-carrying portion of the action is now free and may be removed. Any one oit'the valve-actions may thus be removed, independently of all the others. Or, an entire row of separate valveactions may be removed by first disconnecting the necessary flexible tracker-tubes, then unscrewing the thumb-nuts 56 at each end of the section to be removed, and then pulling the released channel-rail, with the actions connected thereto, forward away tron: the vertical supportiug-members 10 and 11.

The movable wall of the pneumatic carries at its outer end a finger 37 on which normally rests the abstract rod 38 of the player-action. Said pitman is guided in stationary horizontal guides 39. To prevent dropping of the abstract-rod out of normal position when the casing 20 and finger 27 are removed, a collar 420 is, fixed to the ab stract-rod above one of the guides 39, and rests on the latter when the support of the finger is removed, said guide 39 and collar 40 thereby holding the abstract-rod up in place, so that the casing and finger may be readily replaced when desired without requiring the abstract-rod to be separately lifted and held back in position to permit replacement.

For replacing the casing 20, it is only necessary to set the same in position below the channelrail 12, and then manually screw the connecting-screw 18 into the cross-bar 17 until the casing is drawn up tightly against the channel-rail. The tracker-tube 42 is then again placed over the nipple 43 and the parts are in their original position for operation.

The valve 23 controls the opening 26 as described, and also controls an opening. at.

from the pneumatic-duct 21 to the atmosphere. Tt is guided and kept in place between said openings by two oppositelyarranged arcuate guides 47 extending for only a portion of the total circumference of the valve and permitting between their spaced ends the necessary flow of air, said guides being supported on the. casing and preferably made integral with the seat 45 of the valve at the opening 26. They are of less height than the duct 21, but of sufficient height to retain and guide the valve both when the same is in upper position for closing the opening 44:, and when in lower position for closing the opening 26. To secure tight closing and prevent deteribration of the valve and its seat, the valve is made of some material which is inert to the corrosive action of the chemicals remaining in the leather of which the valve is formed, as well as resistant to oxidation of corrosion in air. Such a material is common glass. The permanently smooth surface which this material affords, secures superior closing, and

its acid-resistant and non-corrosive properties lengthen the life of the valve and thereby of the action;

In the operation of the instrument, when an opening of the note-sheet passes in register with the opening in the tracker-bar to which the tracker-tube 4:2 is connected, atmospheric air is admitted to said tube 42 and thence below the diaphragm 25. The suction constantly existing in the suctionchamber 1% lifts the diaphragm and the valve, the latter closes the opening 4 1, and the suction extends to the pneumatic, collapsing the same. and the collapsing; operation lifts the abstract-rod and actuates the piano-action. The opening in the note'sheet having passed, atmospheric air is no longer admitted through the tracker-tube and beneath the diaphragm, but in order that the valve may fall it is necessary that the air under atmospheric pressure existing in the tracker-tube and below the diaphragm be drawn oft. For this purpose a bleedeuopening was commonly provided between the suction-chamber and the tracker-duct. For

regulating the passage of air through this opening, according to the present invention, the opening 50 is made of large size, and the effective opening 66 is instead located in the nipple 43, in communication with said opening 50, as shown in Fig. 2. The nipple is frictionally inserted in the casing 20, and when the operator desires to obtain a more rapid return of any valve it is only necessary to remove the nipple 43 by pulling the same out of its socket in the casing, and insert another nipple having a slightly larger opening (36. Thus more air is permitted to pass from the tracker-duct to the suction-chamber. and the descent of the valve is more rapid. Correspondingly. by substituting a nipple having a smaller opening 66. the speed of return of the valve may be diminished. Thereby the effective operation of the valve is best attained and the required speed of return of each valve is independently controlled.

In the player-actions of instruments, as heretofore commonly constructed, transverse rails were employed, in place of all the independent valve-casings of the present invention, and to the lower rail commonly known as the diaphragm-rail or pouch-rail was secured the plurality of independent pneumatics. each pneumatic comprising the two walls and the intermediate collapsible web. Thus there were two thicknesses of material, one the diaphragm-rail, and below it the stationary wall of the pneumatic, which two thicknesses of material are according to the present invention combined in one, namely the portion 65 of the casing 20, which at the same time forms the stationary wall of the pneumatic. In this lower member 65 of the casing, which at the same time is the stationary member of the pneumatic, are located the diaphragm sockets. The additional thickness of material employed in the old construction is therefore by the present invention done away with and the cost thereof saved, and the action is reduced in. size.

For making a tight connection between the channel-rail and the vertical supports 10, 11, and a connectionwhich permits ready detachment of the channel-rail, the bushing 60 is provided with an exterior annular flange 63, which bears at one side against the wall of the vertical member, Within the socket 55. The channel-rail is provided at its rear-face with a packing 61 of leather or other suitable material, which when the channel-rail is screwed in place by its thumb-screws contacts with the annular flange 63, and thereby makes a tight joint. When replacing or removing the channelrail, the same slips readily on and off thebushing which is held by friction in its hole in the vertical member.

The improvements described provide a durable, reliably-act ng pneumatic action for use in pneumatic pianos and other me chanical musical instruments.

It is obvious that the invention is not lim ited to the details of construction shown and described, but changes may be made therein without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. A pneumatic action, comprising a channel-rail having openings therein in communication with the channel therethrough, a plurality of independent valve actions provided with openings registering with the openings of the said channel-rail, a cylindrical member within the said opening of the valve action having a flange engaging the said valve action and extending up;

and a thumb-screw threaded in said cross-f bar and extending through said opening and the channel-rail t0 the outside of the latter and detachably securing the valve-action thereto.

3. A. pneumatic action, comprising a channel-rail, a valve-action secured thereto and; having a bleeder-openingl of greater than normal size between the suction-chamber and the tracker-duct, and a detachable connecting tube inserted in said trackerduct, and having in register with said bleeder-opening a bleeder-opening 0f the size desired, said latter opening being the effective opening: for the flow between the suction-chamber and the tracker-duct and a check-valve for said larger bleeder-opening closing toward the 'trackeriduct.

4. A pneumatic action, comprising a channel-rail, a valve-action secured thereto and having a bleeder-opening of greater than normal size between the suction-chamber and the tracker-duct, and a removable nipple communicating with the tracker-duct and having in register with the said bleederopening a bleeder-opening of smaller size controlling the flow of air between the suc tion-chamber and the tracker-duct and acheck-valve for the larger bleeder-openihg closing toward the tracker-duct.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

HARRY BAINTON. Witnesses:

' F. Hoes,

G. Lows. 

